A red-hot sword was plunged into cold water. This caused the temperature difference between the sword and the water to decrease rapidly.
The relationship between the elapsed time t, in seconds, since the sword was plunged into water, and the
temperature difference, D(t), is modeled by the following function:
9.7
D(t) = 256
a
Complete the following sentence about the decay rate of the temperature difference.
The temperature difference is reduced by a factor of
1
every
4
seconds

the thermometer is precise but not accurate

step-by-step explanation:

14

step-by-step explanation:

14 x 3 = 42

the solution of the equation is 2.23 ⇒ answer b

step-by-step explanation:

* lets revise the meaning of exponential function

- the form of the exponential function is y = ab^x, where a ≠ 0, b > 0 ,  

  b ≠ 1, and x is any real number

- it has a constant base b

- it has a variable exponent x

- to solve an exponential equation, take the log or ln of both sides,  

  and solve for the variable

* lets solve the problem

∵

- the base is 7 and the exponent is x

- insert ㏑ in both sides

∴

- use the rule

∴ x ㏑(7) = ㏑(77)

- to find x divide both sides by ㏑(7)

∴

* the solution of the equation is 2.23 to the nearest 2 decimal places

8

step-by-step explanation: